It is common for rear vision mirrors, particularly those mounted externally of a vehicle to be adjustable about two orthogonal axes. This adjustment can be by remote, manual or electric means, or by directly adjusting the mirror by hand.
Rear vision mirrors normally comprise a mirror body or shell with a mirror located in the shell. A base is separately mounted within the shell and a mirror support is pivotally attached to the base. This allows movement of the mirror support and the attached mirror about the adjustment axes. The base may also be part of the mirror body or shell moulding.
One principal aim is to minimise unwanted vibration or movement of the mirror support with respect to the base portion. Vibration should be minimised regardless of the position to which the mirror support is moved. Ideally, the mirror support should be easily moved to the required position, and once in that position, it should not vibrate or move as a result of forces that would be applied to the mirror during normal use of a vehicle.
Examples of mirror support assemblies incorporating movement prevention devices is shown in U.S. Pat. No. 4,826,305 and International Patent Application No WO 99/00272. Both of the mirror mounts shown in these patent specifications use friction engagement between two surfaces. However, in order to make both arrangements work, a high degree of precision is required in both moulding and mounting of the components, and the arrangements are subject to failure over a period of time as a result of reduced friction as the engagement surfaces wear.
It is an aim of this invention to provide an improved mirror mounting assembly which prevents undesirable vibration and movement of the mirror.